The primary aim of this application is to obtain novel information about chronic pelvic pain of bladder origin (CPPBO) in order to determine the magnitude of the problem and its cost to society. This study builds on our ongoing collaborative work with the NIH Chronic Prostatitis Collaborative Clinical Research Study, in which demographics, risk factors, quality of life, and health resource utilization are being evaluated in men with chronic voiding symptoms and pelvic pain. These studies are ongoing, and we will utilize similar methods in men and women in order to obtain consistent data for comparison between the sexes. The specific aims are: 1) to assess the prevalence and incidence of CPPBO. A clinically useful definition of the syndrome will be described, and this definition will be used to assess the prevalence of the syndrome in a large, diverse patient population. Using the same definition, the incidence of new cases will subsequently be determined over a three-year time period; 2) to determine risk factors for the development of CPPBO. A case-control study will be performed using age- and gender-matched controls in order to evaluate for medical conditions and lifestyle factors which are associated with the syndrome; and 3) to evaluate the effect of CPPBO on patient quality of life and health resource utilization. To conduct this study, two populations will be utilized. A database of patients from the Kaiser Permanente Foundation Hospitals in Oregon will be used to assess population prevalence and incidence rates and direct medical costs. Questionnaires will be mailed to a random sample of the Kaiser Permanente patients to obtain detailed information about symptoms and quality of life (QOL). In addition, patients diagnosed with CPPBO at the Northwestern Memorial Faculty Foundation Urology Clinic will undergo a more extensive questionnaire evaluation to analyze medical and lifestyle risk factors for the presence of CPPBO and to obtain additional QOL and health resource utilization information. Answers from the Urology clinic patients will be compared with those of age-and gender-matched controls in a case-control study design. This project will provide novel, population-based epidemiologic information about chronic pelvic pain of bladder origin in both men and women, and will help to further define the public health burden of this extremely common condition.